Is the Rationale of Anatomical Liver Resection for Hepatocellular Carcinoma Universally Adoptable? A Hypothesis-Driven Review.

Surgical resection is the first-line curative treatment modality for resectable hepatocellular carcinoma (HCC). Anatomical resection (AR), described as systematic removal of a liver segment confined by tumor-bearing portal tributaries, may improve survival by reducing the risk of tumor recurrence compared with non-AR. In this article, we propose the rationale for AR and its universal adoption by providing supporting evidence from the advanced understanding of a tumor microenvironment and accumulating clinical experiences of locoregional tumor ablation therapeutics. AR may be advantageous because it completely removes the en-bloc by interrupting tumor vascular supply and thus extirpates the spreading of tumor microthrombi, if they ever exist, within the supplying portal vein. However, HCC is a hypervascular tumor that can promote neoangiogenesis in the local tumor microenvironment, which in itself can break through the anatomical boundary within the liver and even retrieve nourishment from extrahepatic vessels, such as inferior phrenic or omental arteries. Additionally, increasing clinical evidence for locoregional tumor ablation therapies, such as radiofrequency ablation, predominantly performed as a non-anatomical approach, suggests comparable outcomes for surgical resection, particularly in small HCC and colorectal, hepatic metastases. Moreover, liver transplantation for HCC, which can be considered as AR of the whole liver followed by implantation of a new graft, is not universally free from post-transplant tumor recurrence. Overall, AR should not be considered the gold standard among all surgical resection methods. Surgical resection is fundamentally reliant on choosing the optimal margin width to achieve en-bloc tumor niche removal while balancing between oncological radicality and the preservation of postoperative liver function. The importance of this is to liberate surgical resilience in hepatocellular carcinoma. The overall success of HCC treatment is determined by the clearance of the theoretical niche. Developing biomolecular-guided navigation device/technologies may provide surgical guidance toward the total removal of microscopic tumor niche to achieve superior oncological outcomes.